Various service providers have been acquiring frequency spectrum in various frequency bands based on the availability of wireless communication spectrum in various, relatively limited, geographic regions. A goal of at least some of these service providers is to create a relatively large network by providing service using the available frequency bands which can be acquired from region to region.
Multichannel Multipoint Distribution System (MMDS) band, is a title sometimes used to describe an unconventional band formed by a plurality of different frequency bands in different geographic regions. MMDS enables opportunities for service providers who own the rights to different frequency spectrum in different geographic locations. The MMDS band is unconventional in that a service provider may be assigned different frequency bands in different geographic regions, e.g., cities or states. It is also unconventional in that the carrier frequency to be used may be different in different geographic areas and may be determined by the particular service provider in the region. Thus, there is no single primary carrier, which is known throughout a wide area, e.g., the entire country, to which a mobile can initially tune upon entering a service area to obtain additional carrier and/or band allocation information.
Service providers may deploy the system in different carriers in different areas, depending on spectrum availability. Wireless terminals, which may operate in any number of different areas, have to search and find the available carrier upon entering an area in order to obtain services using the MMDS band. In addition, in FDD (Frequency Division Duplex) systems, the pairing of downlink and uplink carrier frequencies may not be fixed throughout a wide area, e.g., different carriers used for downlink signaling may be associated with different carriers used for uplink signaling in different geographic areas.
It should be appreciated from the above discussion, that the use of different frequency bands and/or carriers in different locations can greatly complicate the task confronting a wireless terminal regarding what frequency band and/or carrier frequency (or frequencies) should be used in a particular geographic region.
Accordingly, there is a need for apparatus and methods that will enable a wireless terminal to quickly and efficiently search and find the carrier frequency or frequencies and/or the frequency band to be used for communications purposes in a particular geographic region.